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		<title>three.js webgl - animation - basic</title>
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			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> webgl - animation - basic use
		</div>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';

			import Stats from 'three/addons/libs/stats.module.js';

			let stats, clock;
			let scene, camera, renderer, mixer;

			init();

			function init() {

				scene = new THREE.Scene();

				//

				camera = new THREE.PerspectiveCamera( 40, window.innerWidth / window.innerHeight, 1, 1000 );
				camera.position.set( 25, 25, 50 );
				camera.lookAt( scene.position );

				//

				const axesHelper = new THREE.AxesHelper( 10 );
				scene.add( axesHelper );

				//

				const geometry = new THREE.BoxGeometry( 5, 5, 5 );
				const material = new THREE.MeshBasicMaterial( { color: 0xffffff, transparent: true } );
				const mesh = new THREE.Mesh( geometry, material );
				scene.add( mesh );

				// create a keyframe track (i.e. a timed sequence of keyframes) for each animated property
				// Note: the keyframe track type should correspond to the type of the property being animated

				// POSITION
				const positionKF = new THREE.VectorKeyframeTrack( '.position', [ 0, 1, 2 ], [ 0, 0, 0, 30, 0, 0, 0, 0, 0 ] );

				// SCALE
				const scaleKF = new THREE.VectorKeyframeTrack( '.scale', [ 0, 1, 2 ], [ 1, 1, 1, 2, 2, 2, 1, 1, 1 ] );

				// ROTATION
				// Rotation should be performed using quaternions, using a THREE.QuaternionKeyframeTrack
				// Interpolating Euler angles (.rotation property) can be problematic and is currently not supported

				// set up rotation about x axis
				const xAxis = new THREE.Vector3( 1, 0, 0 );

				const qInitial = new THREE.Quaternion().setFromAxisAngle( xAxis, 0 );
				const qFinal = new THREE.Quaternion().setFromAxisAngle( xAxis, Math.PI );
				const quaternionKF = new THREE.QuaternionKeyframeTrack( '.quaternion', [ 0, 1, 2 ], [ qInitial.x, qInitial.y, qInitial.z, qInitial.w, qFinal.x, qFinal.y, qFinal.z, qFinal.w, qInitial.x, qInitial.y, qInitial.z, qInitial.w ] );

				// COLOR
				const colorKF = new THREE.ColorKeyframeTrack( '.material.color', [ 0, 1, 2 ], [ 1, 0, 0, 0, 1, 0, 0, 0, 1 ], THREE.InterpolateDiscrete );

				// OPACITY
				const opacityKF = new THREE.NumberKeyframeTrack( '.material.opacity', [ 0, 1, 2 ], [ 1, 0, 1 ] );

				// create an animation sequence with the tracks
				// If a negative time value is passed, the duration will be calculated from the times of the passed tracks array
				const clip = new THREE.AnimationClip( 'Action', 3, [ scaleKF, positionKF, quaternionKF, colorKF, opacityKF ] );

				// setup the THREE.AnimationMixer
				mixer = new THREE.AnimationMixer( mesh );

				// create a ClipAction and set it to play
				const clipAction = mixer.clipAction( clip );
				clipAction.play();

				//

				renderer = new THREE.WebGLRenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.setAnimationLoop( animate );
				document.body.appendChild( renderer.domElement );

				//

				stats = new Stats();
				document.body.appendChild( stats.dom );

				//

				clock = new THREE.Clock();

				//

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			function animate() {

				const delta = clock.getDelta();

				if ( mixer ) {

					mixer.update( delta );

				}

				renderer.render( scene, camera );

				stats.update();

			}

		</script>

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